I. Field of the Invention
This invention relates to CRT terminals, more specifically, the power supplies which drive the terminals and the other digital circuits therein.
II. Prior Art
There are many ways to drive CRT terminals known in the art. The most common method is to couple two power supplies together. One power supply provides regulated DC voltages which drive all the digital circuits such as a microprocessor, screen memory, and communication circuitry within the CRT terminal and the other power supply provides the CRT bias voltages and the power for the deflection yoke which control the CRT's beam's deflection on the screen. Each power supply has similar control switching, start up and protection components. As a result, there is a great redundancy in the two power supply circuits used to drive the CRT terminal.
Therefore, a single power supply that can drive the multiple power regulated outputs and a stable current sawtooth waveform suitable for driving a magnetic deflection yoke would be a substantial advance in the art.